Ecological regression explained

Ecological regression is a statistical technique which runs regression on aggregates, often used in political science and history to estimate group voting behavior from aggregate data.^[1]

For example, if counties have a known Democratic vote (in percentage) D, and a known percentage of Catholics, C, then running a linear regression of dependent variable D against independent variable C will give D = a + bC. If the regression gives D = .22 + .45C for example, then the estimated Catholic vote (C = 1) is 67% Democratic and the non-Catholic vote (C = 0) is 22% Democratic. The technique has been often used in litigation brought under the Voting Rights Act of 1965 to see how blacks and whites voted.^[2]

See also

• Ecological correlation
• Ecological fallacy

Further reading

• Brown . Philip J. . Clive D. . Payne . Aggregate Data, Ecological Regression, and Voting Transitions . Journal of the American Statistical Association . 1986 . 81 . 394 . 452–460 . 2289235 . 10.1080/01621459.1986.10478290. advanced techniques
• Book: King, Gary. Martin Abba Tanner. Ori Rosen. Ecological Inference: New Methodological Strategies. 2004. Cambridge University Press. 9780521542807.
• Kousser . J. Morgan . Ecological Regression and the Analysis of past Politics . Journal of Interdisciplinary History . 1973 . 4 . 2 . 237–262 . 202265 . 10.2307/202265 . with guide to the literature

Notes and References

1. Gelman . Andrew . Park . David K. . Ansolabehere . Stephen . Price . Phillip N. . Minnite . Lorraine C. . 2001 . Models, assumptions and model checking in ecological regressions . Journal of the Royal Statistical Society, Series A (Statistics in Society) . 164 . 1 . 101–118 . 10.1111/1467-985x.00190 . 0964-1998.
2. Book: Jacob S. Siegel. Applied Demography: Applications to Business, Government, Law and Public Policy. 2002. Emerald Group . 557. 9780126418408.